正极材料LiFe_(0.5-x)Mn_(0.5)Ni_xPO_4/C的制备与性能

Synthesis and performance of cathode material LiFe_(0.5-x)Mn_(0.5)Ni_xPO_4/C

通过机械活化、高温固相反应,合成了正极材料LiFe0.5-xMn0.5NixPO4/C(x=0、0.1)。XRD、SEM分析表明:材料均为纯相的橄榄石型,镍的掺杂使晶胞参数有所减小,并使二次颗粒更小、更均匀。循环伏安测试结果表明:镍的掺杂减轻了材料的电化学反应极化。以0.1C、0.2C、0.5C、1.0C在2.5～4.2 V充放电,LiFe0.4Mn0.5Ni0.1PO4/C的首次可逆放电比容量分别为149.0 mAh/g、145.8 mAh/g、133.1 mAh/g和124.6 mAh/g。

LiFe0.5-xMn0.5NixPO4/C （ x = 0,0.1 ） cat hode materials were prepared by mechanical activation and high temperature solid-state reaction. XRD and SEM analyses indicated that the materials were both pure olive-type, the doping of Ni decreased the lattice parameters and made the secondary particle smaller and more homogeneous. Cyclic voltammetry test results showed that the doping of Ni reduced the electrochemical reaction polarization of the material. When charge-discharge at 0. 1 C,0. 2 C, 0.5 C and 1.0 C in 2.5 - 4.2 V, the initial reversible specific discharge capacity of LiFe0.4 Mn0.5 Ni0.1 PO4/C was 149.0 mAh/g, 145.8 mAh/g, 133.1 mAh/g and 124.6 mAh/g, respectively.